Blowpipe apparatus and process



July 14, 1942. w JONES 2,289,786

BLOWPIPE APPARATUS AND PROCESS Filed Oct. 19, 1940 INVENTOR HOMER W.JONES ATTORNEY July m, I i942 UNITED STATES PATENT .oFFicE BLOWPIPEAPPARATUS AND PROCESS Homer W. Jones, Westiield, N. J., assignor to Theldilrlilde Air Products Company, a corporation of Application October19, 1940, Serial No. 361,821 1 Claims. (01.148-9) This invention relatesto.blowpipe' apparatus and process, and particularly to an improvedmethod of and means for inhibiting slag accumulations on the lower edgeof a steel body adjacent the kerf resulting from a thermochemicalsevering operation, e; g., when cutting a ferrous metal body with anoxy-acetylene blowpipe.

- In the course of manufacture of ferrous metal bodies, such as steelproducts, it is often necessary to cut the steel bodies, such as bloomsor billets, into shorter lengths before further processing, because ofthe excessive length that would be obtained in rolling{ to the finishedsize without such severing operation. Ordinarily, when steel parts, suchas billets, bloom and bars, are severed with a cutting blowpipe prior tosuch finishing operation, it is necessary that the cut surfaces be freeand clean of slag and other oxidic formations, so that all surfaces ofthe resulting ieces will besmooth, because, in subsequent processingorrolling of the' resulting pieces, all lateralsurfaqes of the piecesmust be'smooth, otherwise slag .will be rolled into the piece andproduce] a, defective product. However, especially in cutting steel at arelatively high temperature', such as that used in hot rolling, thethermochemical severing operation is accompanied by an accumulation ofslag along the lower edges of the work adjacent the kerf, which is verydifficult to remove owing to the fact that the slag contains a largepercentage of unoxidized metal.

The main objects of this invention are, therefore, to inhibit theaccumulation of slag on the underside of work adjacent a thermochemical'cut by providing an improved method of and means for producing a smoothand slag-free kerf during the severing operation; to provide novelthermochemical apparatus for controlling slag discharged from the kerfat the underside of work during a thermochemical severing operathe depthof the cut varies from the beginning to the end of the severingoperation. a

In accordance with the invention, there is provided thermochemical meansfor preventing slag from adhering to the underside of a ferrous whichcomprises directing a stream of commer-,

V cially pure oxygengas of suitable velocity against the work surfacesalong both sides of the i cut and causing the stream of oxygen to followthe point of emergence of the slag from the kerf as the cuttingprogresses through the work.

tion; to provide an improved process of controlling slag tending toaccumulate on the lower side of a ferrous metal body beingthermochemically cut; to provide a blowpipe apparatus capable of avariety of uses in thermochemically treating or conditioning a. metalsurface; to provide a novel and emcient blowpipe apparatus forsimultaneously severing a metal'body and eliminating slag accumulationalong the resulting cut and the edges adjoining the same; and to provideapparatus which enable two blowpipes freely to spread apart orautomatically approach each other and constantly keep both at the properrelation to the work, while performing a severing operation in which thethickness of the bar or The blowpipe apparatus preferably comprises, incombination, two blowpipes adapted to perform, a work severingoperation, means supporting the blowpipes, and means for moving theblowpipes with respect to work to be severed, and means for causing thetwo blowpipes to V spread apartfreely and automatically approach eachother in constant relation to the work while performing a severingoperation in which the thickness of the work or the depth of the cutvarie from the beginning to the end of the severing operation.

The novel features which are believed to be characteristic of thisinvention are set forth with particularity in the appended claims. Theinvention itself, however, together with further objects thereof willbest be understood by reference to the specification taken in connectionwith the accompanying drawing.

Fig. 1 is a fragmentary view in side elevation of. apparatus embodyingthe invention and constructed to perform the improved method; and

Fig. 2 is a fragmentary view in section of the apparatus, taken on line2-2 of Fig. 1.

Referring to the drawing, the apparatus illus-- trated by way of examplecomprises a horizontal main supporting arm I which is secured to anysuitable propelling means, such as motor-propelled carriage 2 mounted onand movable along a track 3. Depending from the main supporting arm Iand rigidly secured thereto isa vertical supporting arm 4. A horizontalblowpipe supporting bar 5 is pivoted to the arm 4 by a pin 6,

to permit vertical displacement of a cutting blowpipe I as it ipropelled over the work, such as a steel bar W to be severed. Dependingobliquely from the bar are two arms 9, 9 having bearings l0, lll'attheir free outer ends, on which are journalled guide rolls H, H forguiding the blowpipe I over the bar W.

Y The blowpipe I is secured to one end of the bar 5 by a circumferentialclamp 12 so that its nozzle I3 is maintained in fixed position withrespect to the axis of rollers l-l. When the nozzle I3 is properlyspaced from the work W, forward movement of the main arm I will causethe blowpipe I to traverse the work W while the guide rollers l Imaintain the nozzle I3 spaced a substantially constant distance from thecurved upper surface of the work W. To counterbalance a portion of theweight of the blowpipe 1 and the guides, a counterweight I4 is securedto the opposite end of the bar 5, thereby reducing the force required todisplace the apparatus forwardly during the process of severing the barW.

A horizontal member I5 is pivoted to the vertical arm 4 by apin- Hi, tocarry at one end a blowpipe I! having a nozzle adapted to deliver a lowvelocity oxygen jet. The purpose of the blowpipe IT, in the illustratedform of the invention, is to prevent slag from clinging to the lateralsurfaces along both edges of the cut, so that such slag will not berolled into these surfaces later, and so that a later and separateoperation will not be necessary to scrape or chip the slag accumulationsoff such lateral surfaces.

Pivoted by a pin H! 'to the member I5 is a carriage comprising a wheelsupporting member l9 having two ears 20, 20 extending outwardlytherefrom and carrying wheels 2|, 2|. The arrangement is such thatforward movement of the barl will, therefore, cause wheels 2| to moveforwardly and, by virtue of a counterweight 22 on the opposite end ofbar l5, thewheels 2| will follow the curved underside of the work W andat the same time maintain a substantially constant vertical relationshipof the blowpipe IT with the cutting nozzle I3. The oxygen jetblowmovement is so controlled that the oxygen stream emanating therefromis constantly maintained substantially at a fixed angle, preferablytangent, to the curved under surface of the round bar W at the emergingpoint P of the slag S as the cutting progresses through the work W.

During the cutting operation, both the slag controlling blowpipe l1 andthe cutting blowpipe I travel at equal speeds about the work W, theblowpipe ll emitting a stream of low velocity oxygen tangent to thepoint P from which the slag is leaving kerf K, the arrangement beingsuch that all of the slag S is oxidized and blown free from the basemetal, leaving the surfaces Although the apparatus and method of thisinvention are disclosed for use in severing round stock, the principlesof the invention are also applicable in the cutting of stock of otherconfiguration, such as rectangular or square stock.

The blowpipe apparatus may also be used for thermochemical operationsother than cutting and slag controlling For example, the blowpipe I! maybe used for flame machining or treating an undulating or curved ferrousmetal surface by virtue of its novel supporting apparatus which acts tokeep the blowpipe at a substantially fixed angle with respect to thework surface as it is moved thereover.

I claim: 1. Blowpipe apparatus comprising,' in combination, a support, ahorizontal member pivoted to said support for-tilting movement about ahorizontal axis, a blowpipe carriage pivoted to one end of said memberfor tilting movement about a horizontal axis, said carriage comprising apair of eccentric wheels adapted to engage the surface of work, such asa round bar of ferrous metal, and follow the contour thereof when saidsupport is moved'horizontally with respect to such work, a counterweighton the other end of said member, and a blowpipe mounted on said carriagefor delivering a jet at a substantially fixed angle with respect to thesurface of such work by virtue of the Contact of said eccentric wheelstherewith in rolling thereon.

'2. An apparatus for cutting cylindrical bars of I ferrous metalcomprising, in combination, an oxy-fuel gas cutting blowpipe, means forsupporting said cutting blowpipe for causing it to followtheuppersurface of a cylindrical bar while discharging an oxy-fuel gascutting stream downwardly to form a kerf in said bar, a slag controllingblowpipe having a nozzle for directing a soft oxygen jet at the point ofemergence of the slag from such kerf and substantially tangentially tothe surface of said bar, means supporting pipe I! is so secured to thecarriage l9 and its' said nozzle for causing said soft oxygen jet tofollow, the lower surface of said bar in tangential relation thereto,means for propelling said cutting blowpipe and said nozzle in unisontransversely of said bar to sever the same while preventing slag fromaccumulating on the surface of said bar adjacent the cut, said oxygenjet being directed toward and progressively following the point ofemergence of slag from the kerf produced by said cutting blowpipe, saidnozzle supporting means comprising a support, a horizontal memberpivoted to said support .for tilting moveof the work W adjacent the cutsmooth and'entirely free of objectionable accumulations of slag andother oxides that may be formed. Such slag accumulations ordinarilycling to .the sides of the kerf K along the underside of the work Wmerit about a horizontal axis, a nozzle carriage pivoted to one end ofsaid member for tilting movement about a horizontal axis, said carriagecomprising a pair of wheels adapted to engage the curved bottom surfaceof said bar and follow the contourthereof When'said support is movedhorizontally with respect to such work, and a counterweight on the otherend of said member, said nozzle being mounted on said'carriage fordelivering said soft oxygen jet substantially tangentially with respectto the curved bottom surface of such bar by virtue of the rollingengagement of said wheels with said bar.

3. An apparatus for cutting solid bars of ferrous metal. comprising, incombination, an oxyfuel gas cutting blowpipe, means for supporting saidcutting blowpipe for causing it to' follow the upper surface of a solidbar while discharging an having a nozzle for directing a jet at thepoint of emergence of the slag from such kerf and at an acute angle tothe surface of said bar, means cutting medium and a jet of oxidizinggas; and,

- while so advancing said medium and said jet, di-

supporting said nozzle for causing said Jet to fol v the surface of saidbar adjacent the cut, said jet being directed toward and progressivelyfollowing the point of emergence of slag from the kerf produced by saidcutting blowpipe, said nozzle supporting means comprising a support, ahorizontal member pivoted to said support for tilting movement about ahorizontal axis, a nozzlecarriage pivoted to said member for'tiltingmovement about a horizontal axis, said carriage being adapted to engagethe bottom surface of said bar and follow the contour thereof when saidsupport is moved horizontally with respect to such work., said nozzlebeing mounted on said carriage for delivering said jet at an acute anglewith respect to the bottom surface of such bar.

t. An apparatus for cutting solid bars of ferrous metal comprising, incombination, an oxyfuel gas cutting blowpipameans for supporting saidcutting blowpipe for causing it to follow the upper surface of a solidbarwhile discharging an oxy-fuel gas cutting stream downwardly to form akerf in said bar, a slag controlling blowpipe having a nozzle fordirecting a soft oxygen jet at the point of emergence of the slag fromsuch kerf and at an acute angle to the surface of said bar, meanssupporting said nozzle for causing said soft oxygen jet to follow thelower surface of said bar in substantially fixed angular relationthereto, and means for propelling said cutting blowpipe and said nozzlein unison transversely of said bar to sever the same while preventingslag from accumulating on the surface of said bar adjacent the cut, saidoxygen jet being directed toward and progressively following the pointof emergence of slag from the kerf produced by said cutting blowpipe,said last-named means comprising means for causing said blowpipe andsaid nozzle to spread apart freely and automatically approach each otherin constant relation to the bar while performing the cutting operationin which the thickness of the bar and the depth of the cut varies fromthe beginning to v the end of the cutting operation.

5. A process of thermochemically cuttinga a solid ferrous metal barwhich comprises simultaneously advancing, along a plane extendingtransversely of said bar, both a thermochemical recting said cuttingmedium against successive exterior surface portions of said bar alongaline extending along the outside of the bar from one side of the bar tothe other side thereof to form a kerf through said bar, and alsodirecting said jet across exterior surface portions of said bar at thesuccessive points of emergence of the slag from said kerf while thelatter is being formed.

6. A process of thermochemically cutting a solid cylindrical bar offerrous metal which comprises directing a thermochemical cutting mediumagainst successive exterior surface portions of said bar along asemi-circular line extending from a point on one side of said bar to adiametrically, opposite point on the other side of said bar, to form akerf through said bar; directing a separate jet of oxidizing gastangentially across the surface of said bar at successive points ofemergence of slag from said kerf while the latter is being formed; andsimultaneously advancing both said cutting medium and said jet along theplane of said kerf and transversely of said bar while moving such mediumand jet apart during the first half of the advance of said medium alongsaid line and moving such medium and Jet toward one another during thesecond half of the advance of said medium along said line. i

7. Apparatus for thermochemically cutting a solid ferrous metal barwhich comprises a blowpipe for delivering a thermochemical cuttingmedium; pivotally-mounted means for supporting said blowpipe andconstructed and arranged to positioned relatively to successive portionsof the exterior surface of said bar against which such medium isdelivered to form a, kerf through said bar; a nozzle for delivering ajet of oxidizing gas;

pivotally-mounted means for supporting said nozzle and constructed andarranged to engage successive portions of the exterior surface of saidbar to maintain said nozzle uniformly positioned so as to direct suchjet across exterior surface portions of said bar at the successivepoints of emergence of the slag from said kerf while the latter is beingformed; and mechanism for si- 7 multaneously advancing both of theaforesaid pivotally-mounted'means as well as said blowpipe planeextending transversely of said bar. Y

' HOMER W. JONES.

